Sex hormones Flashcards
What is the definition of puberty?
Maturation of Reproductive Organs
Production of Sex-Steroids E.g. Oestradiol / Testosterone
Develop Secondary Sexual Characteristics
Attain capability to Reproduce
What are the 5 stages of breast development?
1-Elevation of papilla only
2-Breast bud with elevation of breast and papilla and enlargement of areola
3-Further enlargement of breast and papilla with no separation of their contours
4-Projection of areola and papilla to
form a secondary mound
5-Mature breast, projection of papilla only as areola conforms to breast contour
PBFAM
What are the 5 stages of male genitalia development?
1-Testes, penis, and scrotum
same size as early childhood
2-Early enlargement of testes 2-6 cm3; scrotal skin reddens
and changes in texture
3-Penis lengthens;
testes enlarge 6-12 cm3;
growth of scrotum
4-Further penile and scrotal growth;
testes 12-15 cm3
5-Genitalia adult in size and shape,
Testes >15 cm3
What are the 5 stages of pubic hair growth?
1-Vellus hair no different from abdominal hair
2-Slightly pigmented,
downy hair
3-Darker, coarser,
more curled hair
4-Adult pubic hair that does not reach thighs (axillary hair)
5-Adult hair now on thighs
ADCAT
What is adrenarche and when does it start?
Adrenal androgen production
-Starts ~2 years before gonadarche
What are the effects of oestradiol?
Breast Development
Hair Growth -
Pubic, Axillary
Sweat Gland Composition -
Skin oiliness / Acne
Changes to external genitalia
What are the effects of testosterone?
Deepening of Voice
Hair Growth -
Pubic then Axillary, facial
Sweat Gland Composition -
Skin oiliness / Acne
Changes to external genitalia
Between what ages do girls and boys go through puberty?
Boys:9-14
Girls:8-13
What the the pre and post pubertal testicular volumes?
Pre-4mls
Post-15mls
What is the first and late sign of female puberty?
First: Thelarche
Late: Menarche
What is gonadarche?
Activation of the HPG(Hypothalamic pituitary gonadal) axis
What is GnRH release like?
Pulsatile
What is the early and late onset of puberty coined as?
Early: Precocious
Late: Delayed
What changes occur during minipuberty, what is its purpose and when does it occur?
Occurs in infancy, includes
Testicular descent
Penile length
Sertoli cell maturation
Behavioral effects
-Is early activation of the HPG axis
What occurs to GnRH secretion during puberty?
Increased nocturnal GnRH pulsatility
When does menarche occur in regards to thelarche?
~2.3yrs after Thelarche.
Soon after Peak Height Velocity (PHV)
Mean Age 12.7 years (Range 10.7-16.1 years)
What is secondary amenorrhoea?
Common for Periods to be irregular / anovulatory for first 18months.
Periods start but then stop for at least 3-6 months
What is primary amenorrhoea?
Menarche later than16yrs
Amenorrhoea def
- No periods for at least 3-6 months.
- or up to 3 periods per year.
Oligo-menorrhoea def
Irregular or Infrequent periods >35day cycles
or 4-9 cycles per year.
What are the 3 phases of ovulation?
Follicular phase
Ovulatory phase
Luteal phase
What occurs during the follicular+ovulatory phase of the menstrual cycle?
FSH rises, 2-3 follicles start to grow
-These produce E2 and Inhibin B
These reduce FSH by -ve feedback
This restricts the FSH window and non-dominant follicles undergo atresia
Dominant follicles-Are less dependent on FSH
A dominant ‘graafian’ follicle emerges, E2 levels soar, causing it to switch to +ve feedback
High E2 causes LH surge
LH spike causes ovulation
What occurs to the corpus luteum after ovulation and how can this be used as evidence of ovulation?
The corpus luteum begins to produce progesterone and E2
-Mid-luteal progesterone is evidence of corpus luteum perforation, therefore release of an oocyte
What is the most likely time to get pregnant?
Days 14-16
-Right after ovulation